Hamamatsu-Photonics K.k.

Hamamatsu Photonics Kabushiki Kaisha

Precise Gauges Co., Ltd.

Soei Patents, Trademark & Law

Musubu Koishi

Akira Takeshima

Yutaka Tsuchiya

Akira Takahashi

Yoshihiko Mizushima

Motoyuki Watanabe

Hironori Takahashi

Katsuyuki Kinoshita

Manabu Yasukawa

Kouichi Shirakawa

Shinichiro Aoshima

Hirofumi Kan

Yoshihisa Warashina

Hirotoshi Terada

Kenji Suzuki

Mitsunori Nishizawa

Yoshinori Inagaki

Kazuhiko Wakamori

Chiyoharu Horiguchi

Akihiro Sawaki

Shingo Minamino

Etsuo Tsujimura

Tomoyoshi Hara

An optical connector comprises a sleeve with a flange provided at one end face of a hollow cylinder, a collimator lens, which is press-fitted into or fitted by insertion into the sleeve to be thereafter adhered and fixed to the sleeve, and an optical fiber, which is fusion-bonded at the end face of the collimator lens on the opposite side to the flange side in such a state that the collimator lens is fixed into the sleeve, wherein the end face of the flange is machined to a plane perpendicular to an optical axis, and the collimator lens has a focal position at the end face on the opposite side to the flange side.

Optical connector

An optical device fabrication method capable of fabricating optical devices with high precision and reliability in a simple process and at a low cost. The method of splicing a first optical device and a second optical device to fabricate a third optical device includes the steps of: (a) starting heating of an end surface of the first optical device to soften the end surface; (b) pushing the second optical device into the softened end surface to splice the first optical device and a joint surface of the second optical device to each other; (c) pulling back the second optical device to arrange the joint surface of the second optical device onto or outside of the end surface of the first optical device; and (d) terminating heating of the end surface to fix the first and second optical device spliced to each other.

Optical device and fabrication method and apparatus for the same

Light emitted from a light source module and introduced to an optical fiber is detected with a photodetector. An amplification unit amplifies an output from the photodetector. Using a piezoactuator, the light source module is subjected to reciprocal scanning by repeating one-dimensionally in the X axis direction. In this way, one-dimensional optical intensity distribution in the X-axis direction is obtained based on an output of an amplification unit obtained in accordance with the reciprocal scanning. Based on the one-dimensional optical intensity distribution in the X-axis direction, relative positions between the light source module and the optical fiber are adjusted.

Method and apparatus for core alignment between optical components

A semiconductor light amplifier device emits, from an exit end processed to yield no reflection, outgoing light with a light quantity corresponding to a driving signal input from a driving circuit. This outgoing light irradiates, by way of an optical system, an object to be measured; whereas the reflected light, scattered light, and diffracted light generated by the object trace back the optical system and are made incident on the exit end of the semiconductor light amplifier device in a feedback manner as return light. Accordingly, the light amplifier device performs optical amplification as the return light is incident thereon, thereby increasing the light quantity of the outgoing light. This change in light quantity of the outgoing light is detected by the light-receiving device and output therefrom as a light-receiving signal. Thus, as the relationship between the driving signal and light quantity of the outgoing light in the semiconductor light amplifier device changes in response to the light quantity of the return light, an optical characteristic of the object is measured. Therefore, a photodetector apparatus can be obtained, in which, as noise caused by the return light is suppressed, a high S/N ratio and a wide dynamic range are attained while a high-speed response is enabled.

Photodetector apparatus

In the light-source position adjustment device, a magnification lens 31 magnifies a light bundle emitted from a light source 50. A half mirror 32 guides the light bundle outputted from the magnification lens system toward the first and second optical paths. An angular shift measuring portion is disposed in the first optical path for detecting emission angle intensity distribution of the light source. A position shift measuring portion is disposed in the second optical path for detecting a magnification image of the light source which is produced on an image plane of the magnification lens. The light source 50 is disposed on a multi-axes stage unit 10 which is driven by a stage drive unit 20. A control portion 40 receives output signals from the angular shift measuring portion and the position shift measuring portion, and determines an amount by which a light-emission direction shifts from the predetermined standard direction and an amount by which a light-generating point of the light source is displaced from the standard position. The control portion 40 outputs control signals to the stage drive unit. Receiving the control signals, the stage drive unit 20 drives the multi-axes state unit 10 so that the light-emission direction be aligned with the standard direction and so that the light-generating point be located on the standard position.

Optical source position adjustment device

In this system, reflected light from an electro-optic probe is detected by a photodetector, and only a voltage signal of a frequency which is an integral multiple of the fundamental frequency of the output voltage from the photodetector is detected. The frequency characteristics of the output voltage from the photodetector can be measured at a high speed and a high accuracy.

Voltage measuring using electro-optic material's change in refractive

An apparatus of this invention emits light onto an EO probe and detects the light reflected by the EO probe by using an MSM photodetector. The MSM photodetector is applied with a voltage of a frequency nf.sub.0 +.DELTA.f.

Voltage measurement system

An optical feedback photodetection apparatus of the present invention achieves high-speed response while minimizing noise to obtain a high S/N ratio and a wide dynamic range. In the apparatus, on the basis of a modulated drive signal from a drive signal output circuit, a semiconductor laser outputs a light beam modulated at a frequency f.sub.0 to irradiate an object to be measured through an optical system, and the light beam reflected by the object is fed back to the semiconductor laser through the optical system. The intensity of the light beam from the semiconductor laser having an optical amplification function varies due to the return light beam. A photoconductive light-receiving device to which a modulated voltage signal at the frequency f.sub.0 from a voltage application unit is applied receives the light beam from the semiconductor laser and having an intensity varying due to the return light beam, thereby performing synchronous detection. A modulated current signal flowing through the photoconductive light-receiving device is converted to a voltage signal by a current/voltage conversion unit, and the low-frequency component of the voltage signal is extracted.

Optical feedback photodetection apparatus

A photoconductive photodetector to which a modulation voltage signal having a predetermined frequency is applied receives a signal to be measured (I.sub.I) while adjusting the phase of a modulation signal by a phase shifter. A current-to-voltage conversion unit extracts a DC component of a current signal generated at the photoconductive photodetector in correspondence with the intensity of a predetermined frequency component of the signal to be measured (I.sub.I) as a voltage signal. The maximum value of DC voltage values (V.sub.O) obtained in every setting operation of a phase adjustment value is identified. The maximum value corresponds a case in which the modulation voltage signal and the predetermined frequency component of the signal to be measured (I.sub.I) are in phase. The intensity of the predetermined frequency component of the signal to be measured (I.sub.I) is calculated. As a result, a high-speed phenomenon can be measured with a high precision.

Synchronous signal detection apparatus with a photoconductive

An excitation light beam intensity-modulated and output from a light-sending unit is irradiated on a target measurement object. A scattered light beam or a reaction light beam is detected by a light-receiving unit through a wavelength selector. The light-receiving unit outputs a signal according to the product of a supplied modulation signal and the received light beam. A processing unit acquires data corresponding to the product value for each type of light, and calculates the decay characteristics of the reaction light beam on the basis of the acquisition result. In this manner, with a simple arrangement, the decay time of a fluorescence sample or the like is precisely measured in a wide frequency range.

Decay characteristic measuring apparatus

An optical frequency mixing apparatus is provided. Mixing of a frequency of an incident light intensity and a frequency (f.sub.3) of an AC signal generated by a signal generator, i.e., product calculation of the two signals is executed by a photoconductive photodetector of a photodetecting unit. This apparatus has a large allowance for unnecessary incident light such as background light and output characteristics having satisfactory linearity with respect to the incident light intensity, and can deeply set gain modulation. One of the frequency components of the sum and difference between the two signals, which is obtained as a result of product calculation, is selected and extracted using a frequency selector. As an incident optical signal, one optical signal whose light intensity has an AC component (frequency=f.sub.1) may be used. Alternatively, two optical signals whose light intensities have different frequencies (frequencies=f.sub.1 and f.sub.2) may be incident on substantially the same photodetecting area of the photoconductive photodetector.

Optical frequency mixing apparatus

Laser light from LD (laser diode) is guided through a fiber to be projected onto a reflector. A receiver detects a return beam of modulated light reflected by the object and outputs a signal reflecting a phase difference between the laser light and the modulation signal. The frequency of the modulation signal is changed based on the signal value so as to finally achieve phase lock. When the phase lock fixes the frequency of the modulation signal, the frequency always corresponds to a distance from LD to the reflector or a group index of a substance filling the optical path. Thus, the distance to the object or the group index of the substance filling the optical path at the time of phase lock can be determined in a simple manner and with a high accuracy, based on the output frequency at the time of phase lock.

Optical measuring apparatus

This invention relates to an optical fiber component characteristics measuring device which can measure with high precision for a short period of time characteristics of the optical fiber component. The optical fiber component characteristics measuring device comprises a plurality of light sources for emitting light of set different wavelengths, optical coupling means for mixing light from the light sources, coupling means for supplying mixed light from the optical coupling means to an optical fiber component to be measured, spectroscoping means for spectroscoping light from the optical fiber component to be measured, and photoelectric means for parallelly detecting spectra of the light of the respective wavelengths outputted by the spectroscoping means and for converting the spectra into electric signals corresponding to the respective wavelengths. On the input side of the spectroscoping means there is provided optical switch means for switching sequentially between that of light outputted from the plurality of output optical fibers of the optical fiber component to be measured, which has one of said different wavelengths. The light from the optical switch means is detected by the spectroscoping means, whereby characteristics of the optical fiber component including a plurality of output optical fibers can be measured.

Apparatus for measuring spectral characteristics of an optical fiber

A feeble light measuring device comprising a photon counting tube, an image detector and a signal processor. The photon counting tube includes a photocathode for generating an electron upon an incidence of light to be measured, an MCP for multiplying the photoelectron from the photocathode and a phosphor screen for converting the photoelectrons multiplied by the MCP into a light image such as luminous spots. The MCP is not saturated by an incidence of single photoelectron. Thus the spread of the luminous spot corresponding to the single photoelectron is very small. The image detector converts the light image from the photon counting tube to electric outputs the signal processor removes noise components of the electric outputs from the image detector to extract signal components of the electric outputs.

Feeble light measuring device

A wavelength of light emitted from a semiconductor laser is shifted to a shorter wavelength with wavelength converting means and the resulting light of a shorter wavelength is applied to a sample. Upon exposure to the light of the shorter wavelength, the sample emits light of interest and its waveform is measured with measuring means. Fundamental wavelength laser light which passes through the waveform converting means is outputted therefrom in synchronism with the light of a shorter wavelength and detected by a first photodetector. The waveform of the light of interest can be measured correctly on the basis of an output signal from the first photodetector.

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Hamamatsu, Japan

Musubu Koishi